Several breached websites are no longer visible after shrinking the browser window

[CiprianGeorgiu]

[Affected versions]:

• Firefox 62.0

[Affected Platforms]:

• Windows 10 x64
• macOS 10.13
• Ubuntu 16.04 x64

[Steps to reproduce]:

1. Navigate to https://fx-breach-alerts.herokuapp.com/
2. Enter the following email address: test@test.com.
3. Click the "Scan" button.
4. Click the "Show More" button.
5. Scroll down until you reach the last breached website.
6. Shrink the browser window.

[Expected result]:

• All the breached websites are successfully displayed.

[Actual result]:

• Some breached websites are no longer visible.

[Regression range]:

• Not a regression.

[Additional info]:

• see screencast: https://drive.google.com/open?id=1GYGwLOVmIg0e9c7Pg6SiyaWJ7p41ZYRF

[CiprianGeorgiu]

This bug is verified fixed on 62.0 using https://fx-breach-alerts.herokuapp.com/, under Windows 10 x64, macOS 10.13 and Ubuntu 16.04 x64.